1. Field of the Invention
The present invention relates to a management system and a management method for managing a production line of a semiconductor device that is produced through a large number of processes.
2. Description of the Related Art
A well-known semiconductor device such as a very large scale integration (VLSI) is completed as a product through a large number of processes. As a production system for the semiconductor device, production means called a job shop system is employed in which same types of manufacturing apparatuses collectively to be laid out in a factory to constitute equipment groups and a substrate that is an object to be processed moves back and forth among those equipment groups to be produced as a product. Note that, in this specification, a manufacturing apparatus includes an apparatus used in an inspection process.
In general, approximately twenty substrates are stored in a carrier, and the carrier is automatically conveyed between each equipment group. With the automation of conveyance, a substrate can be kept away from a worker, yield can be improved and loss of time caused by waiting for a worker at equipment can be eliminated. The conveyed substrate is subjected to desired processing at each manufacturing apparatus.
Manufacturing apparatuses of a semiconductor device are mainly classified into a batch processing type and a sheet processing type.
Since few kinds of semiconductors typified by a memory product are produced in a large quantity in a conventional semiconductor production, the mainstream of a manufacturing apparatus is the batch processing type that is capable of simultaneously processing substrates in the order of a few pieces to 100 pieces. However, with the manufacturing apparatus of the batch processing type, although efficiency of substrate processing is high, it is difficult to keep high process capability and it is also difficult to flexibly cope with production of various types of semiconductors in a small quantity for dealing with diversification of products that is required in the market recently.
On the other hand, in the case of the manufacturing apparatus of the sheet processing type, since substrates can be processed one by one, it is possible to flexibly cope with the production of various types of semiconductors in a small quantity. In addition, the sheet processing type has advantages in that a time period from the time when a substrate is taken out of a carrier until the time when a substrate after processing returns to a predetermined position, a so-called tact time, is short, processing adapted to a state of respective substrates is possible, and a time period after chemical treatment until rinse is short (displacement efficiency is high), and so on. Thus, the sheet processing type is becoming the mainstream of a manufacturing apparatus for a semiconductor.
Processing of a substrate in each manufacturing apparatus may be applied based on a recipe (processing condition) that is different depending on a type or the like of a product to be manufactured. In particular, as demands for the production of various types of semiconductors in a small quantity increase, this tendency is becoming stronger. In such a case, it is necessary to classify substrates for each lot and switch a recipe of the manufacturing apparatus every time the classification of lots is changed. A lot is a collection of substrates that are moved and processed together along a flow of a process and means a unit of production or shipment.
Then, in a factory for producing various types of semiconductor devices, switching of a recipe in each manufacturing apparatus is generally performed using a system for integrating planning, designing and manufacturing based on a common database, a so-called CIM (Computer Integrated Manufacturing) system. By using the CIM system, control for each manufacturing apparatus in a production line can be collectively managed by a computer.
A recipe that should be performed by each manufacturing apparatus is controlled one by one from the computer using the CIM system, whereby it is possible to avoid changing of a recipe of the manufacturing apparatus via manual work as much as possible. Thus, burden on a worker can be reduced and a decline in cleanliness of a clean room due to dusts from people can be controlled.
Note that as necessity for realizing observance of a date of delivery of a trial product or a product of an important customer arises or the tendency of the production of various types of semiconductors in a small quantity becomes stronger, types of lots increase and the number of substrates to be classified into the same lot decreases. In this case, if substrates, all of which are always classified into the same lot, are stored in each carrier, the number of substrates for each carrier decreases and a decline in efficiency of substrate processing is caused. Thus, it is desirable to store substrates classified into different lots in the same carrier together and convey the substrates.
If all the substrates stored in the carrier are classified into the same lot, decision of a recipe or a start order of work of the manufacturing apparatus can be managed by the unit of carrier. However, if substrates classified into different lots are stored in the same carrier together, it is necessary to manage decision of a recipe or a start order of work of the manufacturing apparatus by the unit of substrate.
However, if a recipe or a start order of work of the manufacturing apparatus is managed by the unit of substrate using the CIM system, an amount of information to be managed becomes enormous and burden on a computer to be a host (host computer) increases compared with the management by the unit of carrier. In addition, since it is necessary to exchange data of a large amount of information such as concrete contents of a recipe for each substrate between the host computer and each manufacturing apparatus, transmission and reception of data take time and high performance is required of the host computer.